I wish to study the anatomy and functional neurophysiology of the neural systems that generate horizontal movements of the eyes in vertebrates, using fish as experimental paradigms. By means of intracellular penetration with micropipettes, I shall record from and inject dye into single neurons of the (a) third and sixth nerve nuclei and (b) rhombencephalic motor reticular formation. I shall be concerned with (a) origins as well as shaping of form of eye movement motor pattern and (b) patterns of concommittant efferent sensory outflow.